Optical pointing device with variable focus

摘要

A method and apparatus for focusing an image of a work surface on an optical sensor array in an optical pointing device. Light from a region of the work surface is captured by an imaging system incorporating an optical coupling system and the optical sensor array. The focus of the imaging system is adjusted in accordance with the distance between the optical pointing device and the work surface. The distance may be sensed, or inferred by adjusting the imaging system to maximize the focus of the image.